correct!
now that we know k, we have:do i have to double the 300 as well or just the 100?
now plug in N = 200 (since that is double 100 -- the initial population size) and solve for t
you were just given the 300 to find k, now that you have, forget about it. i believe the question is asking how long it takes to double from the initial population (i may be wrong)
all i know, you only have to use one or the other, not both. if you want to find how long it takes to double from 300, then plug in N = 600 and solve for t, then subtract 5 from the answer